The present invention concerns a combine header for a harvesting machine, comprising a frame, a cutter bar, a conveying device for cut stalk material, and drive devices for driving the cutter bar and the conveying device, and support wheels attached to the outer sides of the combine header for supporting the combine header on the ground.
A combine header of the aforementioned kind is disclosed in U.S. Pat. No. 8,245,489. The combine header is connected by means of an adapter frame to the feed channel of a combine harvester. The feed channel is height-adjustable and the combine header is additionally pivotable and height-adjustable by means of the adapter frame. In addition, the combine header is also supported by support wheels on the ground wherein the support wheels are arranged at a spacing behind the combine header and are height-adjustable. As a result, in this solution three height-adjustable components must be joined with each other in a common control device in order to be able to guide the combine header close to the ground. The support wheels themselves are unsuitable for guiding the combine header close to the ground because they are arranged at a significant spacing away from the cutter bar that is decisive for the cutting function of the combine header. Additional sensing devices are required for sensing the ground contour upstream of or below the combine header and transmit the sensor signals to an electronic control unit that, in turn, must send control signals that effect adaptation of the relative position of the combine header to the ground contour so that the combine header is still maintained at a distance to the ground but close to the ground. Such a solution appears to be very complex.
In particular, it appears to be difficult to combine such a combine header with automatic height control of different combine models of different manufacturers so as to provide proper functionality because they are each provided with different control algorithms with different control strategies, control rates, and control parameters.
It is the object of the present invention to simplify the guiding action of a combine header close to the ground during harvesting.